The electricity production and distribution is facing two major changes. First, the production is shifting from classical energy sources such as coal and nuclear power towards renewable resources such as solar and wind. Secondly, the consumption in the low voltage grid is expected to grow significantly due to expected introduction of electrical vehicles. The first step towards more efficient operational capabilities is to introduce an observability of the distribution system and allow for leveraging the flexibility of end connection points with manageable consumption, generation and storage capabilities. Thanks to the advanced measurement devices, management framework, and secure communication infrastructure developed in the FP7 SUNSEED project, the Distribution System Operator (DSO) now has full observability of the energy flows at the medium/low voltage grid. Furthermore, the prosumers are able to participate pro-actively and coordinate with the DSO and other stakeholders in the grid. The monitoring and management functionalities have strong requirements to the communication latency, reliability and security. This paper presents novel solutions and analyses of these aspects for the SUNSEED scenario, where the smart grid ICT solutions are provided through shared cellular LTE networks.

Today, increasing number of industrial application cases rely on the Machine to Machine (M2M) services exposed from physical devices. Such M2M services enable interaction of physical world with the core processes of company information systems. However, there are grand challenges related to complexity and "vertical silos" limiting the M2M market scale and interoperability. It is here expected that horizontal approach for the system architecture is required for solving these challenges. Therefore, a set of architectural principles and key enablers for the horizontal architecture have been specified in this work. A selected set of key enablers called as autonomic M2M manager, M2M service capabilities, M2M messaging system, M2M gateways towards energy constrained M2M asset devices and creation of trust to enable end-to-end security for M2M applications have been developed. The developed key enablers have been evaluated separately in different scenarios dealing with smart metering, car sharing and electric bike experiments. The evaluation results shows that the provided architectural principles, and developed key enablers establish a solid ground for future research and seem to enable communication between objects and applications, which are not initially been designed to OPEN ACCESSFuture Internet 2014, 6 262 communicate together. The aim as the next step in this research is to create a combined experimental system to evaluate the system interoperability and performance in a more detailed manner.

The number of industrial applications relying on the Machine to Machine (M2M) services exposed from physical world has been increasing in recent years. Such M2M services enable communication of devices with the core processes of companies. However, there is a big challenge related to complexity and to application-specific M2M systems called-vertical silos‖. This paper focuses on reviewing the technologies of M2M service networks and discussing approaches from the perspectives of M2M information

The Internet of Things is taking hold in our everyday life. Regrettably, the security of IoT devices is often being overlooked. Among the vast array of security issues plaguing the emerging IoT, we decide to focus on access control, as privacy, trust, and other security properties cannot be achieved without controlled access. This article classifies IoT access control solutions from the literature according to their architecture (e.g., centralized, hierarchical, federated, distributed) and examines the suitability of each one for access control purposes. Our analysis concludes that important properties such as auditability and revocation are missing from many proposals while hierarchical and federated architectures are neglected by the community. Finally, we provide an architecture-based taxonomy and future research directions: a focus on hybrid architectures, usability, flexibility, privacy, and revocation schemes in serverless authorization.

Figure 1.1.1 Smart city architecture. key areas of the cities, such as power grids, water and underground systems, oil and gas pipelines, railways, roads, schools, hospitals, stations, airports, and so on. The application areas of the smart city are diverse, and they connect every corner of the city to the Internet. This provides global intelligence over the management, and it paves the road for "Internet + Internet of things = smart planet" (Zhang et al., 2010). The smart city is the application of the concept of the smart planet to a specific region. The surveillance of infrastructure and environments of the city with the help of sensor technology achieves intelligent urban management and services (Su et al., 2010). The features of the smart city provide development of efficient urban strategies such as construction of smart homes, wireless cities, and smart transportation systems (Su et al., 2010). The use of IoT to realize the smart city vision brings important challenges. With IoT technology, it is estimated that the number of devices connected to Internet will reach to 16 billion in 2020 (EU, 2010). Due to this increase, wireless data traffic that is being fulfilled in cities will reach excessive levels, and the available spectrum will become scarcer. Ever-growing demand in wireless communications has also increased the spectrum scarcity problem. Furthermore, fixed allocation of the spectrum worsens the problem of inefficient spectrum use. While the licensed spectrum bands are underutilized, the unlicensed ones are crowded, and the wireless communication is no longer feasible in these bands. To overcome the spectrum inefficiency and scarcity problems, CR technology is proposed (Mitola and Maguire, 1999). CR-capable wireless devices can access the licensed spectrum bands opportunistically and hence increase the spectrum utilization efficiency (Haykin, 2008). On the other hand, wireless nodes in these systems are resource constrained. Even though the majority of sensor nodes have duty cycling, a conventional battery in a sensor node depletes in less than a year. Therefore, an auxiliary or even a completely distinct source, such as heat, light, motion, and electromagnetic (EM) waves must be exploited to ensure sensors' operation. In this regard, EH technologies come into prominence to build wireless sensor networks (WSNs) that are free from battery constraints (Sudevayalam and Kulkarni, 2011). Hence, these challenges promote